D'oh! Just destroyed my Crystalyte motor... and my bike

32 posts / 0 new
Last post
CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
D'oh! Just destroyed my Crystalyte motor... and my bike

A while ago I bought a Trek 7.2 FX (steel fork, aluminum frame, and yes the fork passes the magnet test) and slowly converted it with the "Phoenix Racer" (Crystalyte X-5) kit from electricrider.com. I finally got it working and functional late last night and took it for a very brief nighttime ride, though I barely used the motor and mostly pedalled since it was dark and I had no reflectors, let alone lights! Also I wanted to see how easy it was going manual, and it turned out to be effortless.

Today was a beautiful day so I got ready to take it out again, though I noticed the front bolts were somehow loose even though I'd tightened them tightly before. Oh, by the way, I was not using the hook thing for the fork because it did not fit. The dropouts for my fork are not vertical like the kit assumes; they're diagonal, and the only way to fit the wheel was to remove that thing and even the guards around the wires.

Anyway I retightened the bolts with a pair of pliers and tried to take it out, but the motor wouldn't work! Then I noticed the wires had been twisted around the axle 270 degrees, so I removed the bolts and discovered the axle had rotated 90 degrees within the fork, stretching it out so the dropout is almost square. D'oh!

So now I have a dead motor and a dangerous fork that I need to replace. The axle (I don't know the correct terminology) is evidently alot tougher than the steel fork. And I never even got to take it for a real drive yet.

NickF23
Offline
Last seen: 11 years 5 months ago
Joined: Saturday, November 18, 2006 - 10:25
Points: 184
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

As a former x5 (rear wheel) owner this doesn't surprise me. Its a heavy and poweful motor. I find the whole idea of putting one in a front wheel a little strange. I would have thought the bare minimum necessary would have been a torque arm.

If I were in your position I would contact electric rider and ask for a replacement/refund. What voltage were you running at?

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

I bought it from them 5-6 months ago, and it was my fault that it broke. I used ordinary pliers to tighten the bolts, but never thought twice about that fact that while they felt very tight, they were easy to untighten. Properly tight bolts would be difficult to loosen. Lesson learned. My roommate mentioned lock-bolts, in which there's a plastic disk under the bolt, and the bolt buries into the disk as you tighten it, making it very difficult even to purposely loosen. Also I'll get really long pliers.

I went with the front wheel because I still plan on pedaling often and I prefer the mechanics of manual rear drive, powered front drive, rather than some hybrid setup on the same wheel. Also the front wheel is easy to remove if I need to work on it. Besides, this particular bike has an aluminum frame but a steel fork, so if I wanted a rear-wheel drive then I'd basically need to buy a new bike.

Torque arm was what I meant by "hook thing" and it was not possible to use. But ElectricRider said they'd been testing a bike with no torque arm and found it reliable, as long as the bolts were properly tight.

NickF23
Offline
Last seen: 11 years 5 months ago
Joined: Saturday, November 18, 2006 - 10:25
Points: 184
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

" But ElectricRider said they'd been testing a bike with no torque arm and found it reliable, as long as the bolts were properly tight."

maybe they did. This issue's been raised on the power-assist group with various people coming up with good reasons why x5 in front wheels are a bad idea. And quite a few fork failures and spinning motors and disappointed ebikers, though thankfully no serious accidents yet. Even if the bolts are tight there is still an awful lot of rotational force on a small piece of steel. I think you can get a torque arm from www.teamhybrid.co.uk that might well work for the x5. Even then make sure you have some pretty strong front forks to fix it to.

Are you going to try to rewire the motor yourselves (might not be that hard) or just return it/buy another one?

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

What power-assist group? Can you give me the link?

Regarding rear wheels, ElectricRider's website says it's only for 26" wheels and mine are 700C (about 29") although I'd have to buy a new bike anyway if it came to that. How is the rear wheel installed? I don't know much about bike repair/assembly.

NickF23
Offline
Last seen: 11 years 5 months ago
Joined: Saturday, November 18, 2006 - 10:25
Points: 184
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

http://tech.groups.yahoo.com/group/power-assist/messages. you can search the archives but there are a lot of messages!

You can get a rear motor into most wheel sizes. Buzz on the old forums (ypedal) on this one knows more about this sort of thing. I'm not trying to say that front wheel hub motors are unworkable, just that they need to be propertly secured ie a good torque arm.

Teffo
Offline
Last seen: 13 years 7 months ago
Joined: Monday, February 19, 2007 - 21:09
Points: 5
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

I have been running the same motor as you on 84v 20a/hr and on a steel fork to which have I welded (TIG) on custom made SS double thick fork dropouts myself. (I'll show photos when I get them.) The fork was mofidied heavily to accept the torque of the 503. The torque arm that came with the motor went into the trash the moment I saw it - looked like a piece of junk. I know from my experience these front mount X5 motors should not be used by those without prior e-bike experience due to the very likely potential of catastrophy on a stock fork. I run my motor hard, and accumulate over 10,000 miles per year + another 7,000 I ride on my road bike. (I'm a hard core UCI cat. 3 racer) - I got 40,000 e-miles in the last 4 years running my 408 - thus when I sold it and bought a 503, I knew it was a different beast. I took precautions. My commute is 48 miles to work each day and hazards abound everywhere. I'm extremely concerned about fork breakage (never was with the 408) and check the bolts every week. Also, you mentioned - you use pliers! - very unwise.

Teffo

84V X503 FRONT MOTOR CUSTOM FORK CUSTOM HOME MADE 20Ahr NIMH

[i]84V X503 FRONT MOTOR CUSTOM NIMH[/i]

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Well my problem was simply that the bolts were not so tight that they were difficult to remove, but they should have been. So I bought heavy-duty pliers about two feet long, and I bought "Loctite", a sort of glue specifically for metal bolts for exactly this purpose (the Home Depot salesman, and the packaging, recommend them for automobile wheels, small engines, etc.) which I hope will be enough.

But in case it isn't, I'm thinking I'll place a wrench under the bolt, and thread alot of wire in the ring-end of the wrench, around the fork. In this really bad MSPaint:

TorqueArm.png

The arrow is forward, the dark red object is my fork (note the diagonal dropout direction), the black object is the motor's bolt, and the blue object is the wrench, with the wire being gold. Of course this doesn't look secure with the wrench so far away from the fork, so I may have to try to bend it, but I don't know how.

...by the way, the angles in this mspaint are pretty accurate.

mf70
Offline
Last seen: 2 years 8 months ago
Joined: Friday, December 1, 2006 - 09:01
Points: 712
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

The torque arm that came with the motor went into the trash the moment I saw it - looked like a piece of junk.

Granted, I haven't fooled with "front wheel drive" yet, but doing without the torque arm just because it seemed too lightly built is a little confusing.

As you found out, you'll need to brace against that torque somehow - either by tightening the axle nuts nose-bleedingly tight, or by a small torque link, acting with FAR better leverage. If there's no anchor on the forks to fit the link, it would be sufficient to add a clamp to the fork tube; with the proper mechanical advantage, the forces won't be great.

I know what I'd choose.

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

I think you're confused; Teffo was the one who ignored the torque arm, but he made himself an alternative. The reason I didn't use mine was because it did not fit. It requires the dropout to be vertical, but as you can see from my picture, mine's diagonal.

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

I've been thinking about it more, and realized the torque would move the wrench clockwise in my picture, making the wire useless. Hm.

Sturdly
Offline
Last seen: 9 years 3 months ago
Joined: Sunday, November 19, 2006 - 13:46
Points: 144
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

DANGER DANGER Will Robinson pain and suffering is rapidly approaching !

Please tell me this whole thread is a joke. I would hate to see someone get seriously injured.

There is a time and place for rat bike engineering and this is most definitely not it.

Ever hear of natural selection?

You could always move the wrench to the back side of the fork and reverse its holding direction.

ILBCNU
Offline
Last seen: 12 years 6 months ago
Joined: Saturday, December 9, 2006 - 18:56
Points: 67
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Because the dropouts are already toast why not twist the axle so the wrench is in line with the fork and place a clamp on it. After all the wrench is what is going to keep the axle from rotating not the dropouts.

Just a thought,
ILBCNU

Chas S.
Moderator Team Captain

Teffo
Offline
Last seen: 13 years 7 months ago
Joined: Monday, February 19, 2007 - 21:09
Points: 5
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

In my case I modified the dropouts to be about 1cm thick. A local shop plasma cut some SS steel dropouts shaped the same as the existing dropout then I TIG welded the pieces in. It's about as thick as my Yamaha's YZF R6. Then with a 22mm tightened the nuts on evenly. I did notice that the motor axle stub is not the same diameter on each end, so the dropouts were modified to acommodate this size. From what I can tell, there's no way for it to turn without snapping 1cm ss steel on each end. Of course this is just an example of what can be done. The torque of this motor (and the weight) is huge, and any slack will shear open the dropouts very quickly. I'm also a engineer/scientist, so this is purely my experience talking. I also know a good deal about car restoration and metal fab, and enjoy tinkering with my e-bike. If your dropouts are toast, then please be careful. Go to http://wheelgoods.com/pro325321.html and buy a good fork.
Teffo

84V X503 FRONT MOTOR CUSTOM NIMH

[i]84V X503 FRONT MOTOR CUSTOM NIMH[/i]

mf70
Offline
Last seen: 2 years 8 months ago
Joined: Friday, December 1, 2006 - 09:01
Points: 712
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

You're right. I didn't spot that there were TWO people doing basically the same thing.

The point is leverage. Pick the two smallest children you know, and put them on a seesaw. Now stand at the pivot and try to stop the seesaw from moving. This is what leaving the link out and relying on immense pressure on the axle nut is doing. Yes, with enough pressure you will succeed, but you are getting VERY close to the strength of the metal. There are several points that could fail. I don't know about your setup, but two-wheelers often have a flat on the threads to stop torque. If you over-tighten the nut, you risk either stripping the axle nut and losing ALL attachment of the axle (double plus ungood) or merely shearing the axle slot in the fork to round and wrapping the motor, as you saw.

Now walk out to one of the children on that seesaw. With two fingers you can hold them wherever you like. This is what that torque tube is doing in the design.

If the link doesn't fit, make something that does. That's what has to happen in adapting a design. You don't leave the brakes off because the ones in the box don't fit right, do you?

Mark

NickF23
Offline
Last seen: 11 years 5 months ago
Joined: Saturday, November 18, 2006 - 10:25
Points: 184
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

I just had a look at electric rider website. Does the torque arm even come as standard?

Teffo, is the torque arm really bad?

This is pretty shocking stuff. Electric rider seem to be marketing these kits as consumer products. Its not surprising people do daft things like tighten with pliers, not everyone's from a technical/engineering background. I recenlty got a powabyke electric bike with a front wheel motor, it has a fraction of the torque of those X5 motors yet it still comes with a built in torque arm. Its really not such a hard thing to make/sell or advise on but its not even mentioned on their site and I couldn't find much reference in their owners manual.

Soooner or later someone is going to get seriously hurt maybe even killed and it will be a completely unnecesary death. Cue greiving parents launch campaigne for something to be done about 'dangerous electric bikes'. Cue regulators banning ebikes or massive regulation like we have in europe.

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Yes it comes with a torque arm, but it did not fit my fork because my dropouts were not vertical. Look:

BadWheel_1.jpg

The red arrow indicates the direction of the dropouts; the blue arrow is the direction of the axle bolt with the torque arm inserted. They're very different so I could not place the bolt into the dropouts; I had to remove the torque arm. I *might* be able to fit it with the replacement fork I'm buying, though I'm not sure.

Fechter
Fechter's picture
Offline
Last seen: 11 years 8 months ago
Joined: Friday, November 17, 2006 - 07:01
Points: 199
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

It seems like it would have been good if they made it more adaptable.
It might be possible to detach (or cut off) the end of the torque arm and re-attach it so it lines up better.
Another possible approach would be to bend the end of the torque arm so it can pass over the fork and try to attach the clamp on the other side.

Lessss
Offline
Last seen: 12 years 10 months ago
Joined: Friday, November 17, 2006 - 04:21
Points: 34
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

BadWheel_1.jpg

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Heh, that won't work. Keep in mind the motor will try to rotate the axle clockwise in those pictures, which in your picture will just cause the torque arm's loop around the fork to just slide down; it won't prevent the axle from spinning in the dropouts given the force exerted by the motor.

Sturdly
Offline
Last seen: 9 years 3 months ago
Joined: Sunday, November 19, 2006 - 13:46
Points: 144
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Set up like the picture you could drill an eighth inch hole through both the bracket and fork leg. Then install a roll pin through the works. The bracket won't go anywhere after that.

Lessss
Offline
Last seen: 12 years 10 months ago
Joined: Friday, November 17, 2006 - 04:21
Points: 34
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

So how is the rebuild going?

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

I'm still waiting for the replacement motor; it took over three weeks for the store to get it, but they have it and hopefully I'll receive it from FedEx within a week.

I found a suitable replacement fork, though it's thinner than the previous one and I had to file the dropouts to enlarge them, but it's a straight fork so the torque arm will fit (I verified with the broken motor). It turned out to be difficult to find a straight rigid steel fork with vertical dropouts that fits 700C wheels.

Lessss
Offline
Last seen: 12 years 10 months ago
Joined: Friday, November 17, 2006 - 04:21
Points: 34
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

So what is happening with the old motor?

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Oh, nothing, it's just sitting in my garage. I'll sell it or something, if someone feels like fixing it or parting it, once I have my new motor here and working.

Lessss
Offline
Last seen: 12 years 10 months ago
Joined: Friday, November 17, 2006 - 04:21
Points: 34
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Well like I said I'll take it if you can't sell it. Mailing to NB Canada will cost enough as it is so I can't offer much for it' Worst case I use the magnets for my fridge.

Fechter
Fechter's picture
Offline
Last seen: 11 years 8 months ago
Joined: Friday, November 17, 2006 - 07:01
Points: 199
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

OK, Lesss has first dibs, but I'd love a trashed motor if the price is right. I don't know where you live, but I might be local.

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Same state but not actually local -- I'm in San Diego.

CGameProgrammer
Offline
Last seen: 12 years 4 months ago
Joined: Friday, February 16, 2007 - 18:21
Points: 46
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Well the new motor works; I'm still waiting for a tire (700x50 is not common; had to order online) but the old motor is up for grabs. It's laced in a rim so you get that too. I'm selling it for the cost of shipping plus $20. I think shipping via FedEx Ground is in the neighborhood of $20, probably less. I also have the Bontrager 700x25 tire for it, which has barely been used, which will be another $10 if anyone wants it. Tire shipping would cost nothing if shipped with the motor of course.

Would anyone want the motor for that amount? The damage is likely minimal; the last time it worked, I was standing next to the bike, holding it in place, and gave a very quick jab of the throttle, which propelled the bike as expected a few inches forward, but that was the last time it ever worked. I guess holding the bike put enough resistance against moving forward that the motor instead just counterrotated in the dropout. Anyway I can't even figure out how to open up the motor so this is just speculation.

jb
Offline
Last seen: 13 years 4 months ago
Joined: Sunday, May 27, 2007 - 02:17
Points: 1
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

I'm in San Diego, and I'm interested in your motor. Do you still have it?

cerewa
Offline
Last seen: 12 years 2 months ago
Joined: Saturday, November 3, 2007 - 06:46
Points: 32
Re: D'oh! Just destroyed my Crystalyte motor... and my bike

Pliers are a terrible way to attach bike wheels (even non-motorized ones)

you should use an adjustable wrench or a non-adjustable wrench. A small adjustable wrench provides more torque (and does less damage to your nuts and bolts) compared to an extra-large pliers.

Pages

Log in or register to post comments


Who's online

There are currently 0 users online.

Who's new

  • hippidave
  • rvair19
  • Nicosp
  • VoltLurker
  • Greatwhite

Customize This